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Nanostructured metal-nitrides have attracted tremendous interest as a new generation of catalysts for electroreduction of CO2, but these structures have limited activity and stability in the reduction condition. Herein, we report a method of fabricating FeN/Fe3N nanoparticles with FeN/Fe3N interface exposed on the NP surface for efficient electrochemical CO2 reduction reaction (CO2RR). The FeN/Fe3N interface is populated with Fe−N4 and Fe−N2 coordination sites respectively that show the desired catalysis synergy to enhance the reduction of CO2 to CO. The CO Faraday efficiency reaches 98% at −0.4 V vs. reversible hydrogen electrode, and the FE stays stable from −0.4 to −0.9 V during the 100 h electrolysis time period. This FeN/Fe3N synergy arises from electron transfer from Fe3N to FeN and the preferred CO2 adsorption and reduction to *COOH on FeN. Our study demonstrates a reliable interface control strategy to improve catalytic efficiency of the Fe–N structure for CO2RR. Understanding and controlling chemical environment of metal-N-catalysts is of great importance. In this work, the authors reveal FeN/Fe3N interface with Fe-N4 and Fe-N2 coordination sites for enhanced electrochemical CO2 reduction to CO. [ABSTRACT FROM AUTHOR]

We report a new strategy to prepare a composite catalyst for highly efficient electrochemical CO2 reduction reaction (CO2RR). The composite catalyst is made by anchoring Au nanoparticles on Cu nanowires via 4,4′‐bipyridine (bipy). The Au‐bipy‐Cu composite catalyzes the CO2RR in 0.1 m KHCO3 with a total Faradaic efficiency (FE) reaching 90.6 % at −0.9 V to provide C‐products, among which CH3CHO (25 % FE) dominates the liquid product (HCOO−, CH3CHO, and CH3COO−) distribution (75 %). The enhanced CO2RR catalysis demonstrated by Au‐bipy‐Cu originates from its synergistic Au (CO2 to CO) and Cu (CO to C‐products) catalysis which is further promoted by bipy. The Au‐bipy‐Cu composite represents a new catalyst system for effective CO2RR conversion to C‐products. [ABSTRACT FROM AUTHOR]

We report a new strategy to prepare a composite catalyst for highly efficient electrochemical CO2 reduction reaction (CO2RR). The composite catalyst is made by anchoring Au nanoparticles on Cu nanowires via 4,4′‐bipyridine (bipy). The Au‐bipy‐Cu composite catalyzes the CO2RR in 0.1 m KHCO3 with a total Faradaic efficiency (FE) reaching 90.6 % at −0.9 V to provide C‐products, among which CH3CHO (25 % FE) dominates the liquid product (HCOO−, CH3CHO, and CH3COO−) distribution (75 %). The enhanced CO2RR catalysis demonstrated by Au‐bipy‐Cu originates from its synergistic Au (CO2 to CO) and Cu (CO to C‐products) catalysis which is further promoted by bipy. The Au‐bipy‐Cu composite represents a new catalyst system for effective CO2RR conversion to C‐products. [ABSTRACT FROM AUTHOR]

We report a facile method for assembly of a monolayer array of nitrogen-doped graphene (NG) and nanoparticles (NPs) and the subsequent transfer of two layers onto a solid substrate (S). Using 3 nm NiPd NPs as an example, we demonstrate that NiPd-NG-Si (Si=silicon wafer) can function as a catalyst and show maximum NiPd catalysis for the hydrolysis of ammonia borane (H3NBH3, AB) with a turnover frequency (TOF) of 4896.8 h−1 and an activation energy ( Ea) of 18.8 kJ mol−1. The NiPd-NG-S catalyst is also highly active for catalyzing the transfer hydrogenation from AB to nitro compounds, leading to the green synthesis of quinazolines in water. Our assembly method can be extended to other graphene and NP catalyst materials, providing a new 2D NP catalyst platform for catalyzing multiple reactions in one pot with maximum efficiency. [ABSTRACT FROM AUTHOR]

A facile approach to bimetallic phosphides, Co-Fe-P, by a high-temperature (300 °C) reaction between Co-Fe-O nanoparticles and trioctylphosphine is presented. The growth of Co-Fe-P from the Co-Fe-O is anisotropic. As a result, Co-Fe-P nanorods (from the polyhedral Co-Fe-O nanoparticles) and sea-urchin-like Co-Fe-P (from the cubic Co-Fe-O nanoparticles) are synthesized with both the nanorod and the sea-urchin-arm dimensions controlled by Co/Fe ratios. The Co-Fe-P structure, especially the sea-urchin-like (Co0.54Fe0.46)2P, shows enhanced catalysis for the oxygen evolution reaction in KOH with its catalytic efficiency surpassing the commercial Ir catalyst. Our synthesis is simple and may be readily extended to the preparation of other multimetallic phosphides for important catalysis and energy storage applications. [ABSTRACT FROM AUTHOR]

Advances in chemical syntheses have led to the formation of various kinds of nanoparticles (NPs) with more rational control of size, shape, composition, structure and catalysis. This review highlights recent efforts in the development of Pt and non-Pt based NPs into advanced nanocatalysts for efficient oxygen reduction reaction (ORR) under fuel-cell reaction conditions. It first outlines the shape controlled synthesis of Pt NPs and their shape-dependent ORR. Then it summarizes the studies of alloy and core-shell NPs with controlled electronic (alloying) and strain (geometric) effects for tuning ORR catalysis. It further provides a brief overview of ORR catalytic enhancement with Pt-based NPs supported on graphene and coated with an ionic liquid. The review finally introduces some non-Pt NPs as a new generation of catalysts for ORR. The reported new syntheses with NP parameter-tuning capability should pave the way for future development of highly efficient catalysts for applications in fuel cells, metal-air batteries, and even in other important chemical reactions. [ABSTRACT FROM AUTHOR]

We report a new strategy to prepare a composite catalyst for highly efficient electrochemical CO2 reduction reaction (CO2RR). The composite catalyst is made by anchoring Au nanoparticles on Cu nanowires via 4,4′‐bipyridine (bipy). The Au‐bipy‐Cu composite catalyzes the CO2RR in 0.1 m KHCO3 with a total Faradaic efficiency (FE) reaching 90.6 % at −0.9 V to provide C‐products, among which CH3CHO (25 % FE) dominates the liquid product (HCOO−, CH3CHO, and CH3COO−) distribution (75 %). The enhanced CO2RR catalysis demonstrated by Au‐bipy‐Cu originates from its synergistic Au (CO2 to CO) and Cu (CO to C‐products) catalysis which is further promoted by bipy. The Au‐bipy‐Cu composite represents a new catalyst system for effective CO2RR conversion to C‐products. [ABSTRACT FROM AUTHOR]

We report a new strategy to prepare a composite catalyst for highly efficient electrochemical CO2 reduction reaction (CO2RR). The composite catalyst is made by anchoring Au nanoparticles on Cu nanowires via 4,4′‐bipyridine (bipy). The Au‐bipy‐Cu composite catalyzes the CO2RR in 0.1 m KHCO3 with a total Faradaic efficiency (FE) reaching 90.6 % at −0.9 V to provide C‐products, among which CH3CHO (25 % FE) dominates the liquid product (HCOO−, CH3CHO, and CH3COO−) distribution (75 %). The enhanced CO2RR catalysis demonstrated by Au‐bipy‐Cu originates from its synergistic Au (CO2 to CO) and Cu (CO to C‐products) catalysis which is further promoted by bipy. The Au‐bipy‐Cu composite represents a new catalyst system for effective CO2RR conversion to C‐products. [ABSTRACT FROM AUTHOR]

We report in this article a detailed study on how to stabilize a first-row transition metal (M) in an intermetallic L10-MPt alloy nanoparticle (NP) structure and how to surround the L10-MPt with an atomic layer of Pt to enhance the electrocatalysis of Pt for oxygen reduction reaction (ORR) in fuel cell operation conditions. Using 8 nm FePt NPs as an example, we demonstrate that Fe can be stabilized more efficiently in a core/shell structured L10-FePt/ Pt with a 5 À Pt shell. The presence of Fe in the alloy core induces the desired compression of the thin Pt shell, especially the two atomic layers of Pt shell, further improving the ORR catalysis. This leads to much enhanced Pt catalysis for ORR in 0.1 M HClO4 solution (at both room temperature and 60 °C) and in the membrane electrode assembly (MEA) at 80 °C. The L10-FePt/Pt catalyst has a mass activity of 0.7 A/mgPt from the half-cell ORR test and shows no obvious mass activity loss after 30 000 potential cycles between 0.6 and 0.95 V at 80 °C in the MEA, meeting the DOE 2020 target (<40% loss in mass activity). We are extending the concept and preparing other L10-MPt/Pt NPs, such as L10-CoPt/Pt NPs, with reduced NP size as a highly efficient ORR catalyst for automotive fuel cell applications. [ABSTRACT FROM AUTHOR]

Review: 118 refs. [ABSTRACT FROM AUTHOR]